The paper gives a briefly introduce about the recently experimental studies for the dynamic property of rock joints based on SHPB tests. The joints include artificial joints filled with sand and clay and artificial non-filled joints cut on granite and aluminum alloy blocks. The experimental method for wave separation is explained for the modified SHPB test with short rock bars. The influence factors on the dynamic property of rock joints are investigated, such as the water content, the thickness of filling layer, the pulse loading intensity, the loading rate, the joint matching coefficient and the spatial geometry of joint surface.
The mechanical behavior of rock mass is significantly affected by the vastly existing discontinuities, primarily joints. One of the main tasks in the fields of rock mechanics and engineering is to well understand the mechanical properties of the discontinuities and their effects on rock mass behavior. The discontinuities are generally called as joints of rock masses. In nature, there are many kinds of rock joints. As for the filling material, the rock joints are divided into filled joints with filling material or non-filled joint. The physical properties of rock joints affect the normal and shear strength, deformability, permeability, etc. The test results of Pyrak-Nolte et al. (1990) showed that the dynamic stiffness of rock joints was always higher than the quasistatic stiffness, and the dynamic stiffness was related to the stress and saturated conditions.
